"I'm pretty sure that we will try to tread lightly to get compliance at first," he said Monday, three days after the appellate court in Santa Ana published its ruling as a statewide precedent. "We're not in the business of hassling people. ... Officer discretion will play a role."

Still, he noted, the ruling overturned a 30-year-old policy that had allowed sunbathers and swimmers to bask unclothed in isolated sections of state beaches from San Diego to Eureka. Park rangers intervened only if someone complained, and then would merely tell the nudist to don a swimsuit or leave.

The ruling doesn't apply to federal parkland such as the Golden Gate National Recreation Area, which includes San Francisco's North Baker Beach and several other Bay Area sites frequented by the unclad, or private land such as a portion of Muir Beach in Marin County. The National Park Service does not prohibit nudity on its land, said Chris Powell, spokeswoman for the national recreation area.

But some popular clothing-optional state beaches, such as Gray Whale Cove south of Pacifica and Red Rock Beach in Mount Tamalpais State Park, will be affected.

Lawyers for the Naturist Action Committee, which sued unsuccessfully to preserve a clothing-optional zone at San Onofre State Beach in Orange County, said they would appeal the ruling to the state Supreme Court and lobby the Parks and Recreation Department to exercise its long-unused authority to designate areas where nudism is allowed.

"It's time for the government to realize that nude sunbathing and skinny-dipping has a long tradition in this country," said Allen Baylis, an attorney and officer of the committee.

California law has long prohibited public nudity in state parks and beaches, except for areas set aside as clothing optional by the Parks and Recreation Department. Violators can be charged with misdemeanors. Baylis said a typical fine is $500.

A more flexible policy was announced in 1979, by state Parks Director Russell Cahill. He refrained from designating any beaches as clothing optional - saying that would only focus opponents' attention on "what seems to be a victimless crime at worst" - but instead said officers would enforce the anti-nudity law only if a private citizen complained.

As a result, nude sunbathers have been left largely undisturbed in certain areas, including a portion of the San Onofre beach. But in May 2008, state Parks Director Ruth Coleman withdrew San Onofre's status, saying public complaints about nudity and sexual conduct had increased as the local population grew and the beach became a popular site for family outings.

An Orange County judge said Coleman had acted illegally by not submitting her order first to a state administrative agency or seeking public comment. But the Fourth District Court of Appeal said Cahill didn't do that in 1979, either, so the department was free to ignore his policy because it had not been adopted validly.

Edna Kopacz, a lawyer for the Naturist Action Committee, said Monday the group would ask the state's high court to rule that Cahill had substantially complied with state law by holding public hearings and conducting a study before announcing his policy. "People have been relying on it for 30 years," she said.

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